• 한국항공우주학회지
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• 제38권3호
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• pp.288-293
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• 2010

본 논문은 장 단거리 공대공 미사일의 치사율을 계산하고, 대상 미사일의 모델을 구성하여 모의 발사 시험 프로그램을 개발하고자 한다. 신뢰성 있는 치사율을 계산하기 위해서는 신관과 탄두에 대한 많은 자료와 실험이 필요하지만 현실적으로 그런 작업을 수행 하기엔 한계가 있다. 따라서 본 논문에서는 참고문헌[3-6]에서 획득한 치사율에 대한 자료를 분석하여 치사율을 계산하였다. 모의시험을 위한 시뮬레이션 프로그램은 MATLAB/SIMULINK를 이용하여 6 DOF 시뮬레이션 모델을 구성하였으며, 수직, 수평 가속도 피드백을 이용한 자동비행 알고리즘과 PNG(Proportional Navigation Guidance)을 이용한 유도명령 알고리즘, 그리고 시간지연과 오차를 고려한 탐색기(seeker)의 동적 모델을 구성하여 적용하였다. 최종적으로 정면발사, 측면발사, 후면발사의 3가지 경우에 대하여 모의 비행을 수행하여 결과를 정리하였으며, 이때 목표물은 일정한 방향을 가지고 등속비행을 하는 것으로 설계하였다.

• 생약학회지
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• 제38권3호통권150호
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• pp.227-233
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• 2007

Seven compounds were isolated from the n-BuOH soluble fraction of stem of Rhododendron mucronulatum as cytotoxic principles against brine shrimp lethality test. On the basis of spectral data, seven compounds were identified as (-)-catechin (1), (+)-epicatechin (2), taxifolin (3), scopoletin (4), quercetin (5), $taxifolin-3-O-{\alpha}-L- arabinopyranoside$ (6), and astragalin (7). Among tested compounds, $taxifolin-3-O-{\alpha}-L-arabinopyranoside$ (6) exhibited potent activity with $LC_{50}$ value at 4.6 ${\mu}g/ml$.

• Archives of Pharmacal Research
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• 제22권5호
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• pp.524-528
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• 1999

cis-Annonacin (1) and the mixture of (2,4)-cis-and trans-isoannonacins (2 and 3), three known mono-tetrahydrofuran annonaceous acetogenins, have been isolated form the seeds of Annona cherimolia by the use of the brine shrimp lethality test (BST) for bioactivity directed fractionation. Their structures were elucidated based on spectroscopic and chemical methods. 1 showed potent cytotoxicities in the brine shrimp lethality test (BST) and among six human solid tumor cell lines with notable selectivity for the pancreatic cell line (PaCa-2) at about 1,000 times the potency of adriamycin. The mixture of 2 and 3 is over 10,000 times cytotoxic as adriamycin in the pancreatic cell line (PaCa-2). All of the compounds are about 10 to 100 times as cytotoxic as adriamycin in the prostate cell line (PC-3).

• Archives of Pharmacal Research
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• 제24권4호
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• pp.300-306
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• 2001

A novel and two known bioactive mono-tetrahydrofuran (THF) annonaceous acetogenins, annomocherin (1), annonacin (2) and annomontacin (3), have been isolated from the fractionated ethanolic extracts of the seeds of Annona cherimolia, guided by the brine shrimp lethality test (BST). Their structures were elucidated on the basis of spectroscopic and chemical methods. All compounds have a relative stereochemistry of threo/trans/threo for the mono-THF ring with two flanking hydroxyls. Compound 1 has a double bond at C-23/ 24 of aliphatic chain. Compound 1 was isolated from natural sources for the first time, and was named annomocherin. Two known Compounds 2 and 3 which have never been isolated from this species before, were obtained. Compound 1 exhibited potent and selective cytotoxicities against the breast carcinoma (MCF-7) and kidney carcinoma (A-498) cell lines with 100 to 1,000 times the potency of adriamycin. In brine shrimp lethality test (BST), 1-3 exhibited cytotoxicity.

• ALGAE
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• 제22권3호
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• pp.241-246
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• 2007

Cochtodinium votykrikoides -related red tide is the most notorious tidal bloom, resulting in mass mortality to marineanimals. This study aimed to test the effect of C. polyknkoides on the lethality to Haliotis discus hannai under con-trolled conditions. The oxygen demand of C. polykrikoides increases to reach its peak duhng the night, while the oxy-gen usage by H. discus hannai was continuously decreased with a threshold of 2 mg L U. The addition of C.polykrikoides did not effect the respiration of the H. discus hannai. However, the usage of oxygen by C. polykrikoidesduhng the night may lead to anoxia in the animal. With aeration, the level of dissolved oxygen (D.O.) was between6.06 and 7.28 mg LU; 90% of abalones survived even with a high concentration of C. potykrikoides (9000 cells mL U).Without aeration (3 mg LU of D.O.), however, the H. discus hannai suffocated immediately. Once 20 hours hadelapsed, all of the abalones were dead. The density of the H. discus hannai population contributed to their mortality.Therefore, aeration during the night and maintaining lower abalone densities is the best way to promote the sur-vivorship of H. discus hannai during a C. polykrikoides red tide.

• 대한바이러스학회지
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• 제26권1호
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• pp.67-76
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• 1996

The methods that make Hantavirus grow consist of inoculation into the experimental animals and cultured cells. The cultured cells, such as Vero-E6 and A549 cells, have been usually used for isolation of the virus and the animals, such as mice and rats, are used for large scale preparation of the virus so far. Furthermore, the cell can be used to maintain the virus and assay the infectivity and the animals can be used for the experiment of viral pathogenicity and challenge for assessment of vaccine. Apodemus mice, the own natural host of the virus, has been used for challenge test of Hantaan virus. However it has been pointed out to difficult handling and breeding the animal in laboratory. Therefore, we attempted to establish a new animal model for challenge test at the time of isolation of Maaji virus which is a new hantavirus similar but distinct to Hantaan virus. In suckling hamster, the titer of Maaji virus and the lethality to mice of the virus were increased gradually in the titer and lethality through passage by intracerebral (IC) inoculation. We tried to re-adapt this brain virus to lung of weanling hamster. The brain passaged virus was inoculated into weanling hamster intramuscularly. Again, the titer of the virus in lung was also increased by continuous passage of this virus. This facts could regarded as adaptation to new environment in which the virus proliferates. To identity the virus passaged in hamster with Maaji virus, both of the virus passaged in hamster brain and lung were compared with Maaji virus (MAA-I) and Hantaan virus (HTN 76-118) by means of restriction fragment length polymorphism (RFLP) and slingle strand conformation polymophism (SSCP). As a result, we conclude that Maaji virus could be adapted successfully to weanling hamster through this passage strategy. Utilizing this adapted Maaji virus strain, hamster model is able to be used for challenge test in hantaviral vaccinology and further experiments utilizing hamster system as a rather available and convenient lab animal are expected.

• 대한약침학회지
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• 제17권3호
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• pp.7-15
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• 2014

Objectives: The present study investigated the toxic properties of petroleum ether extract of Wattakaka (W.) volubilis in Wistar female rats. Methods: An in vitro brine shrimp lethality bioassay was studied in A. Salina nauplii, and the lethality concentrations were assessed for petroleum ether extract of W. volubilis. A water soluble portion of the test extract was used in different concentrations from $100-1000{\mu}g/mL$ of 1 mg/mL stock solution. A 24-hours incubation with a 1-mL aliquot in 50 mL of aerated sea water was considered to calculate the percentage rate of dead nauplii with test extract administration against a potassium-dichromate positive control. The acute and the sub-acute toxicities of petroleum ether extract of W. volubilis were evaluated orally by using gavage in female Wistar rats. Food and water intake, body weight, general behavioral changes and mortality of animals were noted. Toxicity or death was evaluated following the administration of petroleum ether extract for 28 consecutive days in the female rats. Serum biochemical parameters, such as alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, total cholesterol, triglyceride, total protein, glucose, urea, creatinine, sodium, potassium and ${\alpha}$-amylase levels, were measured in the toxicity evaluations. Pathological changes in isolated organs, such as the liver, kidneys, and pancreas, were also examined using hematoxylin and eosin dye fixation after the end of the test extract's administration. Results: The results of the brine-shrimp assay indicate that the evaluated concentrations of petroleum ether extract of W. volubilis were found to be non-toxic. In the acute and the sub-acute toxicity evaluations, no significant differences were observed between the control animals and the animals treated with extract of W. volubilis. No abnormal histological changes were observed in any of the animal groups treated with petroleum ether extract of W. volubilis. Conclusion: These results suggest that petroleum ether extract of W. volubilis has a non-toxic effect in Wistar female rats.

• Molecules and Cells
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• 제27권3호
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• pp.345-350
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• 2009

We previously reported that flavone induces embryonic lethality in Caenorhabditis elegans, which appeared to be the result of cell cycle arrest during early embryogenesis. To test this possibility, here we examined whether flavone inhibits the activity of a key cell cycle regulator, CDC-25.1 in C. elegans. A gain-of-function cdc-25.1 mutant, rr31, which exhibits extra cell divisions in intestinal cells, was used to test the inhibitory effects of flavone on CDC-25 activity. Flavone inhibited the extra cell divisions of intestinal cells in rr31, and modifications of flavone reduced the inhibitory effects. The inhibitory effects of flavone on CDC-25.1 were partly, if not completely, due to transcriptional repression.

• 통합자연과학논문집
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• 제7권3호
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• pp.173-182
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• 2014

To simplify the different biological investigation of the methanolic extract and solvent-solvent partitioning of Lablab purpures (L. purpures) bark. In-vitro anti-oxidant study was determined using total DPPH radical scavenging assay. In vitro antimicrobial study was measured by observing zone of inhibition. The cytotoxic activity was studied using brine shrimp lethality bioassay and thrombolytic activity by clot disruption method. The antioxidant potential was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Folin-Ciocalteau reagents using butylated hydroxytolune (BHT) and ascorbic acid as standards. The Aqueous soluble fraction revealed the highest free radical scavenging activity ($IC_{50}=48.76{\mu}g/mL$). The antimicrobial screening of the bark of L. purpures exhibited mild to moderate activity in test microorganisms. The CSF showed the maximum relative percentage inhibition against Salmonella parathyphi (34.2%) for bacteria and C. albicans (28.8%) for fungi whereas, lowest relative percentage inhibition against Sarcina lutea (22.0%) for bacteria and Aspergillus niger (24.4%) for fungi. In the brine shrimp lethality bioassay, The $LC_{50}$ values of Carbon tetrachloride and N-Hexane soluble fraction were found $92.18{\mu}g/mL$, and $68.95{\mu}g/mL$ respectively while the $LC_{50}$ values of standard Vincristine sulphate was $1.37{\mu}g/mL$. The methanolic extract and its organic soluble fractions of Lablab purpureus at concentration 2.0 mg/mL, significantly protected the lysis of erythrocyte membrane induced by hypotonic solution and heat as compared to the standard, acetyl salicylic acid (0.10 mg/mL). The MSF and AQSF produced 61.48 % and 53.75% inhibition of hemolysis of RBC caused by hypotonic solution respectively, whereas acetyl salicylic acid (0.10 mg/mL) showed 76.42%. Ethanol extract of L. purpures and all of its different partitions exhibited moderate thrombolytic activity of 37.25%-2.40%. Very good preliminary screening and simplified experiments were able to show the different biological activity of methanolic extract and its soluble fractions of L. purpures at a time.

• 한국동물학회지
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• 제14권2호
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• pp.75-84
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• 1971

Genetic analysis of a new wing mutant, Surf wings (Srf), was performed. Mutant flies were extracted from a wild population of Drosophila melanogaster at the vicinity of Atomic Energy Research Institute, Seoul in August-September 1969. 1. The distal half of wings of heterozygotes (Srf/+) turned upwards about 40 degree from body axis, but flying ability was not disturbed. They overlap Cy in low frequency when they are grown below $22^{\circ}C$. This resembles with Si or j series, but wing margins are not rolled and diversed. Postscutellars are erected slightly, but they, in general, are not crossed. Any other external pleiotropic effects were not observed. 2. Penetrance and expressivity of both sexes are not complete. Their extents are variable with sex and temperature. These characters show maximum tendencies when the development is made at $22^{\circ}C$ (female: P = 0.996, E = 0.932, male:P = 0.961, E = 0.698). 3. The preliminary locus of Srf was determined to be 66.8 on the right arm of second chromosome by using recessive maker gene cn bw. 4. The homozygous flies(Srf/Srf) have shown perfect lethality. The heterozygotes (Srf/+), on the other hand, have shown to be viable and fertile. Srf chromosomes are kept in a balanced lethal system with Pm chromosomes which are associated with inversions. Hence, it is partially reasonable to suppose that Srf may persist in a natural population by the same mechanism. 5. Allelism test with Cy was also conducted. The fact that combination with Cy in the trans-phase (+ Srf/Cy +) is viable in contrast to the lethality of Srf/Srf and Pm/Pm indicates that Srf and Cy are not functionally allelic.